OBJECTIVES • • • • • • At the end of the lecture, the student should be able to: Define the word ‘artery’ and understand the general principles of the arterial system. Define arterial anastomosis and describe its significance. Define end arteries and give examples. Describe the aorta and its divisions & list the branches from each part. List major arteries and their distribution in the head & neck, thorax, abdomen and upper & lower extremities. List main pulse points. “ARTERIES” • Arteries carry blood from the heart to the body. • All arteries, carry oxygenated blood, EXCEPT the PULMONARY ARTERY which carry deoxygenated blood to the lungs. GENERAL PRINCIPLES OF ARTERIES • The flow of blood depends on the pumping action of the heart. • Arteries have ELASTIC WALL containing NO VALVES. • The branches of arteries supplying adjacent areas normally ANASTOMOSE with one another freely providing backup routes for blood to flow if one artery is blocked, e.g. arteries of limbs. • The arteries whose terminal branches do not anastomose with branches of adjacent arteries are called “END ARTERIES”. End arteries are of two types: Anatomic (True) End Artery: When NO anastomosis exists, e.g. artery of the retina. Functional End Artery: When an anastomosis exists but is incapable of providing a sufficient supply of blood, e.g. splenic artery, renal artery. AORTA • The largest artery in the body • Carries oxygenated blood to all parts of the body • Is divided into 4 parts: 1. Ascending aorta 2. Arch of aorta 3. Descending thoracic aorta 4. Abdominal aorta 2 1 3 4 ASCENDING AORTA • Originates from left ventricle. • Continues as the arch of aorta • Has three dilatations at its base, called aortic sinuses • Branches: Right & Left coronary arteries (supplying heart), arise from aortic sinuses ARCH OF AORTA • Continuation of the ascending aorta. • Leads to descending aorta. • Located behind the lower part of manubrium sterni and on the left side of trachea. 1 • Branches: 1. Brachiocephalic trunk. 2. Left common carotid artery. 3. Left subclavian artery. 2 3 COMMON CAROTID ARTERY • Origin: LEFT from aortic arch. RIGHT from brachiocephalic trunk. • Each common carotid divides into two branches: Internal carotid External carotid EXTERNAL CAROTID ARTERY • It divides behind neck of mandible into: Superficial temporal & maxillary arteries • It supplies: Scalp: Superficial temporal, occipital, & posterior auricular arteries Face: Facial artery Maxilla & mandible: Maxillary artery Tongue: Lingual artery Pharynx: ascending pharyngeal artery Thyroid gland: Superior thyroid artery 8 7 6 4 5 3 2 1 INTERNAL CAROTID ARTERY • Has NO branches in the neck • Enters the cranial cavity, joins the basilar artery (formed by the union of two vertebral arteries) and forms ‘arterial circle of Willis’ to supply brain. • In addition, it supplies Nose Scalp Eye SUBCLAVIAN ARTERY • Origin: LEFT: from arch of aorta RIGHT: from brachiocephalic trunk • It continues, at lateral border of first rib, as axillary artery: artery of upper limb • Main branches: Vertebral artery: supplies brain & spinal cord Internal thoracic artery: supplies thoracic wall ARTERIES OF UPPER LIMB At lateral border of 1st rib At lower border of teres major Opposite neck of radius DESCENDING THORACIC AORTA • It is the continuation of aortic arch • At the level of the 12th thoracic vertebra, it passes through the diaphragm and continues as the abdominal aorta • Branches: Pericardial Esophageal Bronchial Posterior intercostal ABDOMINAL AORTA • It enters the abdomen through the aortic opening of diaphragm. • At the level of lower border of L4, it divides into two common Iliac arteries. • Branches: divided into two groups: • Single branches • Paired branches MAIN BRANCHES OF ABDOMINAL AORTA 1 1 2 2 SINGLE BRANCHES SUPPLYING GASTROINTESTINAL TRACT 3 3 4 PAIRED BRANCHES 5 BRANCHES OF COMMON ILIAC ARTERY • EXTERNAL ILIAC ARTERY: continues (at midpoint of inguinal ligament) as femoral artery the main supply for lower limb • INTERNAL ILIAC ARTERY: supplies pelvis ARTERIES OF LOWER LIMB Femoral Artery Is the main arterial supply to lower limb Is the continuation of external iliac artery behind the midpoint of the inguinal ligament Passes through adductor hiatus and continues as: Popliteal Artery Deeply placed in the popliteal fossa. Divides, at lower end of popliteal fossa into: 1-Anterior Tibial Artery 2-Posterior Tibial Artery PULSE POINTS IN HEAD & NECK PULSE POINTS IN UPPER LIMB PULSE POINTS IN LOWER LIMB THANK YOU